The present invention relates to the field of underwater oil production installations using multiple and varied, electrical and hydraulic interconnections between different sub-assemblies of the underwater station, such as well heads, control modules, manifolds and other units.
Remote-controlled tools have to be used with these interconnections, which are often located at great depths on the sea bed because of their environmental conditions.
When it is necessary to use several connectors because of the number of interconnections, these can be grouped on a single support and operated by a single mechanical-hydraulic system. A sub-assembly of this type comprising several connectors is described as a "multi-connector".
As a variant the multiconnector can be associated with a remote-controlled sub-assembly, which receives from the surface commands of electrical, hydraulic or other origin and is used as an interface for controlling the various sub-assemblies of the station. This remote controlled sub-assembly is commonly known as a remote-controlled "pod".
With this multiconnector associated with this remote-controlled pod the electrical and hydraulic connections between the pod itself, the other bottom sub-assemblies and the surface systems can be established.
According to the standard practices a multiconnector which may be associated with a remote-controlled pod is brought into position with the aid of mechanical-hydraulic actuating systems, which as they are incorporated in the sub-assemblies to be placed on the sea bed, cannot be brought back to the surface at the end of the operation, so that maintaining them at the bottom of the sea involves the danger of their being damaged by the environment.
The object of the present invention is a disconnectable installation tool on an underwater oil production station of a module comprising solely a multiconnector or one associated with a sub-assembly for the remote-control of the control units of the station and which is characterized in that the base of the station is equipped with a set of vertical translation guiding means which are capable of working in conjunction with corresponding contact means which are integral with the module, whereby the module comprises on the one hand a mandrel provided with the means for working in conjunction with the disconnectable gripping means of the tool and on the other hand locking means for the module on the guiding means and whereby the said tool is suspended at a support plate, which has at its periphery means for installing the plate on the upper end of the guiding assembly and means for anchoring the plate on the guiding means, whilst the tool carries on the one hand disconnectable gripping means for the mandrel and on the other means for actuating and disengaging the locking means for the module on the guiding means assembly.
The said vertical translation guiding means which are anchored on the base of the station can take on various forms. They may consist for example of components such as posts or rails extending from the base and rising to the level of the module and the tool and used as guiding slides or ramps, along which the module provided with special contact means such as rollers is guided in vertical translation.
According to the preferred version, these vertical translation guiding means comprise a hollow tube anchored to the sea bed and open at its upper end.
The means of anchoring the plate to the upper part of the tube may consist of three assemblies carried by the plate on its circular periphery and offset by 120.degree., whereby each assembly comprises a hydraulic jack and a locking finger operated in translation by the said jack, whilst in the vicinity of its opening, the tube is provided with anchoring holes designed to receive the said locking fingers.
The plate may carry one or several installation dampers terminating in the shape of a wedge so as to be supported in the notches formed on the circular edge of the tube opening.
With these indexing notches which are designed to receive the positioning wedges of the installation dampers of the plate a correct angular orientation of the jack-lock assemblies in relation to the holes formed in the tube can be achieved.
The disconnectable gripping means of the tool may consist of a connector comprising on the inside of a hollow body, cocking-type pieces formed by the flexible blades of a split ring fitted at their ends with pawls which penetrate a housing formed on the periphery of the mandrel, the said ring being integral with the disengaging blocks adjacent to the hydraulic jacks used for disengaging the connection.
The means of locking the module on the tube wall may consist of sliding bolts and holes formed in the tube wall in the positions corresponding to the location of the said bolts when the connector is connected on the mandrel.
The said sliding bolts may be operated by actuating and disengaging means carried by the body of the connector and consisting for preference of pusher-type hydraulic jacks, the pusher of which terminates in a fork or hook, of which the curved part is directed downwards and operates in conjunction with a shoulder or a stop of the sliding bolt in such a way that the return of the connector interrupts the interaction of the hook and lock and enables it to be released. The upper part of the connector may bear a connection jack supported on the support plate, whereby this jack applies a vertical thrust to the connector after the jack-lock assemblies carried by the support plate have been locked on the tube wall.
It is self-evident that other means of actuating or disengaging the locking and disengaging means apart from hydraulic jacks can be used advantageously.
Other special features of the invention will be found in the following description of an embodiment, which is given by way of a non-restrictive example and which is illustrated by the following drawings.